Resilient anti-vibration sleeves are known, in particular, for use in flexible couplings in exhaust pipes, and they are made from a strip of steel wire knit rolled up to form a cylindrical preform and then compressed axially to obtain a resilient anti-vibration sleeve ready for mounting. Making such a sleeve gives rise to a cohesion problem both during manufacture of the preform where it is necessary to keep the strip of steel wire knit rolled up prior to its insertion in a mold for axial compression, and also during use where the resilient sleeve is subjected to additional axial compression forces that tend to deform the sleeve and cause it to take up a barrel shape with the attendant risk of causing the steel wire knit to unroll in spite of its stitches being tangled together by the inital axial compression of the preform.
To cope with these problems, resilient sleeves have been made in which the cylindrical preform of steel wire knit is kept rolled up either by stitching the end of the strip of steel wire knit, or by stapling the end of the strip of steel wire knit, or else by installing crimping rings, e.g. copper rings. All of these solutions suffer from drawbacks, either to do with cost when manufactured on an industrial scale, or else to do with losing a fraction of the performance of the sleeve, and in particular its elasticity in a longitudinal direction. It has also been envisaged that the cylindrical perform could be wrapped in a very thin metal foil, however this solution is unsatisfactory since even when using a metal foil that is very thin, it reduces the resilient properties of the sleeve too much after it has been compressed axially.
An object of the present invention is to provide a resilient anti-vibration sleeve capable of being made on an industrial scale under satisfactory conditions and having good cohesion, both during manufacture and during use.